This invention relates to liquid containers which are formed from flat blanks having score regions which define fold lines for the blanks and more particularly relates to a novel structure for a scored blank which provides reinforcement at a container bottom horizontal score adjacent the side seam flap to prevent leakage at that point.
Plastic coated cardboard containers formed from prescored blanks are well known and are in common use, for example, for containing liquids such as milk, fruit juice and the like. These containers frequently have a gabled top which is arranged to define a pouring spout when the top is opened. The container is formed from a single prescored blank of a paperboard material that is typically referred to in the trade as food-board and foodboard which is coated with plastic, such as polyethylene, which permits the formation of heat seals to secure together the blank. A single, generally continuous horizontal score extends across the bottom of each of the panels forming the sides of the container and defines respective bottom flaps. The score is made in a conventional manner and generally consists of a U-shaped depression in the blank material. Such blanks are folded and sealed in the form of a container as by heat sealing or gluing or any other desired process.
It has been found that the bottom horizontal score in the region of the side seam flap tends to open or extend fully when the bottom of the container is formed and with pumping action which may occur during transport of the liquid filled container. The opening of the horizontal score can sometimes weaken the corner of the container to the point of failure.